I got Marshall valvestate 8080 and Zoom G1X. Marshall is good amp itself, but I tested it with Zoom. Terrible noise in effect loop, terrible noise in line-in too. I like to use wah-pedal, but is it bad combination or what?
I can't think of any amp-related reasons for the noise. I like the sound of Zooms but you may want to get rid of it and get some analog stomp boxes. A lot of amps just don't like modeling/digital.